Air-line valve.



G. D. HOFFMAN.

7 AIR LINE VALVE.

APPLICATION man MAY 25. 1914.

Patented Mar. 28

Ill

7 I 02760671 for: 'geargc DJfo/f zl/ifnew 60: f7/ 03 I Am UNITED STATES PATENT OFFICE.

GEORGE D. HOFFMAN oF PASADENA, CALIFORNIA, ASSIGNOR T0 HOFFMAN SPECIALTY COMPANY, OF BOSTON, MASSACHUSETTS, A CORPORATION OF MASSACHUSETTS.

AIR-LINE VALVE.

Specification of Letters Patent.

Patented Mar. 28, 1916.

Application filed May 25, 1914. Serial No. 840,764.

steam radiator, the valve casing being connected with a. radiator to receive air, water and steam therefrom, and with a pipe line adapted to conduct the air and water, driven from a radiator by entering steam, out of the apartment in which the radiator is located, the valve having an acting valve member which is automaticallyclosed on a valve seat by the flexible diaphragm of an expansion chamber actuated by an increase of temperature due to the entrance of steam into the valve casing.

One object of the invention is to enable the escape of air and water from a radiator into the casing of-an air line valve to be restricted for the purpose of preventing an objectionably rapid entranceof steam into the radiator, the restriction being preferably variable or capable of regulation when the valve is being tested either before or after its installation for regular use.

Another object of the invention is to enable the valve seat to be accurately adjusted in accordance with factory tests and then provided with a permanent stop which prevents it from being subsequently raised above the desired position determined by the tests. Provision is therefore made for carefully and accurately raising the valve seat of each valve at the place of manufactui e in accordance with the action of the expansion chamber of that particular valve and for preventing an unskilled person from subsequently changing the adjustment by raising the seat to a higher point, it bein; a fact that the diaphragms ofdiifcrent expansion chambers vary as to the amplitude of their valve closing movement, so that it is highly desirable to test each valve and adjust its valve seat before installation and to prevent further raising of the valve seat after the factory tests and adjustment have been effected.

The invention consists in the unprovements which I will now proceed to describ and claim.

Of the accompanying drawings, forming a part of this specification; Figure 1 represents a vertical section of an air line valve embodying my invention; Fig. 2 represents a plan view of the spider hereinafter referred to; Fig. 3 represents a plan view of v the three-armed. spring hereinafter referred to; Flg. 4 represents a side view of the inlet plug shown by Fig. 1; and Fig. 5 represents a sectional view of the inlet nipple,

showing a modified form ofthe restricted port.

The same reference characters indicate the same or similar parts in all the views.

In the drawings, 12 represents the casing of an air line valve, the same being provided at its upper portion with an externally screw threaded inlet nipple 13 adapted to be engaged with a steam radiator 14. The casing includes a. dome-shaped body portion 12 and a head 12 having a screw thread connection with the-body portion, said head being adapted to be connected with a pipe line 15 which conducts air and waterfrom the radiator out of the room in which the radiator is located. As here shown, the head 12 has an external screw thread with which is engaged a union 16, the flange of which engage a flange on an internally threaded fitting 17 into which the end member of the pipe line 15 is screwed. The head 12 contains an outlet for air and water, said outlet being formedby a tubular plug 18 adjustably engaged with the screw threaded wall of an orifice extending through the head, as hereinafter described, the upper end of said plug forming by its intersection with the bore of the plug a valve seat 19.

20 represents an expansion chamber, preferably ofthe form shown by Fig. 1, the upper end of said chamber being seated in a boss 21 at the upper end of the casing. The lower end of the expansion chamber is formed by a flexible diaphragm 22 adapted to be-fiexed downwardly by the expansion by heat of a liquid such as alcohol inclosed' in the expansion chamber, the unexpanded liquid being preferably absorbed by a piece ofblotting paper 23.

24 represents an acting valve member adapted to close the valve seat 19. Said memberis formed on a stud or shank 25 having a head 26 hearing on the diaphragm 22 and on a three-armed spring 27. The arms of said spring bear on a three-armed spider 28 having upstanding cars 29. The spider has a guiding orifice 3O in which the shank 25 is movable. The spring 27 normallyholds the valve open or separated port in the nipple 13, the capacity of said port being variable so that while the port is at-all times restricted so that its capacity is less than the full capacity of the main portion of the bore of the nipple, the capacity of the port can be varied by enlarging it, or by either enlarging or contracting it. The restricted port enables the entrance of steam into the radiator to be retarded so that there will never be an objectionably rapid rush of steam into the radiator, the entrance of steam being at the same rate as the escape of air.

In the preferred embodiment of my invention the nipple 13 is internally, screw threaded and is provided with an externally screw threaded plug 32 having a slot 33 in its outer end adapted to be engaged by a screw driver, the plug being adjustable in the nipple by rotating it. In the periphery of the plug is formed the longitudinal groove 34, the bottom of which is inclined so that the depth of the groove increases from the outer end of the plug inwardly. Said groove and the portion of the wall of the nipple which covers it constitute a restricted port, the capacity of which is variable by adjusting the plug, the capacity of the port being increased by screwing the plug outwardly and decreased by screwing the plug inwardly. More than one groove 34 may be provided, as shown by 'Fig. 1, where two grooves at diametrically opposite sides of the plug are shown. v

Fig. 5 shows a modification of the restricted port, in which the nipple 13 is provided at its outer end with an inwardly projecting flange 35 at the center of which is formed a small orifice 36 constituting the restricted port. lVhile no provision is made for contracting this port, it may be enlarged by the employment of a suitable tool to increase the diameter of the opening 36.

The plug 18 is provided with an adjustable stop collar 37, preferably formed as a nut engaging the external thread of the plug and adjustable lengthwise of ,the plug by rotation thereon, said collar being adapted to abut against a stop face 38 on the head 12' and limit the valve seat raising adjustment of the plug.

It is practically impossible to make the diaphragm 22 of a number of expansion chambers exactly alike, so that they will all have the same amplitude of movement when theliquid in the expansion chamber is expanded by heat. It is necessary therefore for the sake of accuracy to carefully test each valve atthe factory where it is made before installing it. The expert who tests the valve adjusts the plug 18 until the valve seat 19 is raised to the exact location desired, the stop 37 being then adjusted so that it is seated on the face 38, and the stop being then permanently secured or locked to the .plug 18 by solder 39 or otherwise.

, Theplug 18 and collar 37 may now be removed as one piece from the head 12 to permit the cleaning out of the casing, the threaded orifice which receives the plug constituting an outlet for liquid in the casing and for dirt carried thereby. After the cleaning out operation the plug and its collar may be replaced, the collar, locked to the plug, preventing the valve seat from being raised above its former position determined by the factory tests.

Having described my invention, I claim:

1. An air line valve comprising a casing having an outlet, means for connecting the outlet with a pipe line, a valve member adapted to close said outlet and normally held yieldingly open, an expansion chamber adapted to close the valve, and an externally threaded inlet nipple adapted to be screwed into a radiator and provided with internal means adjustable from its inner end to form a variable port governing the escape of air and water from the radiator and the admission of steam thereto.

2. An air line valve comprising a casing having an outlet, means for connecting the outlet with a pipe line, a valve member adapted to close said outlet and normallyheld yieldingly open, an expansion chamber adapted to close the valve, and an externally threaded inlet nipple adapted to be screwed into a radiator and provided with an adjustable plug within its threaded portion and adjustable from the inner end of the nipple and formin a restricted port governing the escape of air and'water from the radiator and the admission of steam thereto, said plug having means for varying the conducting capacity of said port.

n air line valve comprising a casing having an outlet, means'for connecting the outlet with a pipe line, a 'valve member adapted to close said outlet and normally held yieldingly open, an'expansion chamber adapted to close the valve, and an inlet nipple adapted to be connected with a radiator and internally screw threaded, and an exter nally threaded plug engaged with the internal thread of the nipple and provided with a longitudinal gr0ove"in its threaded periphery, said groove increasing in depth from the outerendv of the plug inwardly and forming a restricted port the capacity of which is variable by adjustments ofthe plug.

4. An air line valve comprising a casing having a laterally projecting inlet nipple adapted to be connected with a radiator, a head adapted to be connected with a pipe line and provided with a screw threaded orifice, and witha stop face surrounding said orifice, a threaded tubular outlet plug engaged With-the thread of said orifice, the inner end of said plug forming a valve seat, and-a stop collar on the plug adapted to cooperate with said stop face, said collar being adjustable lengthwise of the plug, and means whereby said collar may be permanently secured to said plug after a suitable seat-raising adjustment of the latter to render said adjustment final, the plug and the collar locked thereto being removable as one part from the head for cleaning purposes and reinsertible to restore the valve seat to its previous adjusted position; the casing being provided internally With a normally open valve member and with an expansion chamber adapted to close the valve member on said valve seat.

In testimony whereof I have alfixed' my signature, in presence of two Witnesses.

. GEORGE D. HOFFMAN. Witnesses:

C. F. BROWN, P, W. Pnzzn'm. 

